The Conversion Unit Problem & Solution

Compromised Septic Tank, Failed soakaway
The Conversion Unit
Wisbech, Cambridgeshire, PE14
30 January, 2015
Dry, Good Ground drainage
5 Person

Building Contractors identified septic tank problems at this property in Cambridgeshire during renovation works. The building contractors recommended the homeowner contact Mantair regarding the septic tank problems.


From our site investigations it was evident that the septic tank problems were being caused due to the soakaway connected to the tank failing. As a result of the soakaway failure the septic tank was flooding, causing the foul drainage from the property to surcharge. The septic tank cover slab also had high levels of sulphate corrosion.

On viewing the Ordnance Survey Geological Map for this area of Cambridgeshire it was evident that the sub-strata was permeable. In view of this and the access restrictions at the property, Mantair engineers recommended upgrading the existing septic tank with a Mantair conversion unit and the construction of a new ‘high level’ soakaway / drainage field. It was also agreed that a new concrete cover slab should be constructed to make the septic tank structurally sound. It was necessary for Mantair engineers to carry out Percolation Tests to determine the porosity of the sub-strata and to obtain the size of soakaway / drainage field required.


Stage 1 – Removal of of the septic tank concrete cover slab and installation of the Mantair conversion unit.


Stage 2 – Construction of the new high level soakaway / drainage field.


Stage 3 – Construction of the new septic tank top and associated ancillary works.

One of the key benefits with installing a Mantair septic tank conversion unit is that it fits within the existing tank removing the need for a new tank to be installed.

Mantair provides a comprehensive septic tank and sewage treatment plant service throughout Cambridgeshire and other surrouding. This includes free site inspections, guidance and advice on the most suitable system for the client’s requirements, complete installation, commissioning and full after sales care.

Did you know that the cost to resolve your septic tank problems may be covered by your existing buildings insurance policy?

Mantair works in partnership with the UK’s leading drainage insurance claims management company to offer our customers a unique insurance claims management service. Providing expertise in managing insurance claims for the costs of repairing or replacing damaged drainage systems, we work on behalf of property owners helping them to save thousands of pounds in resolving their septic tank problems. Read more

Call our team today to find out more about how we can help solve your septic tank problems.  01255 853890.